1. Field of the Invention
Exemplary embodiments of the present invention relate to a backlight assembly and a liquid crystal display having the same, and more particularly, to a backlight assembly capable of preventing a light guide plate from heat generated from a light source unit, and a liquid crystal display having the same.
2. Description of the Related Art
A Liquid Crystal Display (LCD) displays images using electrical and optical properties of liquid crystal. Since the LCD has advantages of slimness, lightweight, low power consumption and low driving voltage as compared with other display apparatuses, the LCD has been extensively employed in various industrial fields.
The LCD includes a liquid crystal display panel, in which liquid crystal is interposed between two transparent substrates and voltage is applied to the liquid crystal to change a direction of liquid crystal molecules to optically display images, and a backlight assembly for providing light to the liquid crystal display panel.
A Cold Cathode Fluorescent Lamp (CCFL), an External Electrode Fluorescent Lamp (EEFL), and a Flat Fluorescent Lamp (FFL) are all examples of possible light sources of a backlight assembly. However, the CCFL represents limitations in terms of high definition, light weight, slim structure and compact size, so a Light Emitting Diode (LED) has been recently used as the light source of the backlight assembly because the LED represents improved performance such as high brightness, long life span and high color purity. In addition, as restriction on dumping of dangerous substances such as mercury has been reinforced, the CCFL is less used, and the LED, which is a more environmental friendly device, is becoming more widely used instead of the CCFL.
The backlight assembly having such an LED as the light source is classified into a direct-type backlight assembly and an edge-type backlight assembly according to the arrangement of the LED and the type of the light guide plate. The direct-type backlight assembly having the LED has a structure in which the LED is disposed in front of the backlight assembly, so the direct-type backlight assembly has a difficulty in achieving slimness and requires a large number of LEDs, increasing the manufacturing cost.
In contrast, the edge-type backlight assembly has a structure in which the LED is mounted at both sides of the backlight assembly and light is introduced into the front surface of the backlight assembly through a light guide plate, so the edge-type backlight assembly may have a thickness smaller than that of the direct-type backlight assembly, thereby realizing the slimness structure.
However, in the edge-type backlight assembly, the light guide plate may be contracted or expanded widthwise along the light guide plate due to thermal deformation. Consequently, the light guide plate may be damaged due to excessive heat.